• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.49-51
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• 2012

In this paper, the integration issue, such as an air-side integration design between the gas turbine and air separation unit, is described and analyzed by the exergy and energy balance of the combined-cycle power block in an IGCC power plant. The results showed that the net power of the system was almost same, but that of the gas turbine was decreased as the integration degree increased. The highest exergy loss was occurred in the combustor of gas turbine, which was affected by the chemical reaction, heat conduction, mass diffusion, and viscous dissipation.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.329-333
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• 1995

The usual methods for the temperature control of mass-concrete structures include the use of low-heat cement, pre-cooling, or pipe-cooling. In order to control the heat of hydration of mass-concrete structures such as massive pier or anchor block, and mat foundation, the pipe cooling method is widely acceptable for pratical use. In this paper, method of analysis using the Finite Element Method was applied to analyze the heat exchange on the field of three dimensional thermal conduction. The result of analysis Well agreed with experimentally measurement data by "KUMATANI". The method of this analysis will be used widely to control the heat of hydration by the pipe cooling in mass-concrete.-concrete.

• Journal of the Korean Society for Heat Treatment
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• v.23 no.6
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• pp.323-330
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• 2010

The present study was motivated by increasing demands on quantitative measurements of the heat flux through the water cooling and quenching process of hot steel. The local heat flux measurements are employed by a novel experimental technique that has a function of high-temperature heat flux gauge in which test block assemblies are directly used to measure the heat flux variation during water cooling and quenching of hot steel. The heat flux can be directly achieved by Fourier's law and is also compared with numerical estimation which is solved by inverse heat conduction problem (IHCP). The high-temperature heat flux gauge developed in this study can be applicable to measure cooling rate and history during the actual cooling applications of steelmaking process. In addition, the measurement uncertainty of heat flux is calculated by a quantitative uncertainty analysis which is based on the ANSI/ASME PTC 19.1-2005 standard.

• Journal of Biomedical Engineering Research
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• v.17 no.4
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• pp.507-514
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• 1996

The automated ECG diagnostic systems in hospital have a low P-wave detection capacity in case of some diseases like conduction block. The purpose of this study is to improve the P-wave detection ca- pacity using wavelet transform. The first procedure is to remove baseline drift by subtracting the median filtered signal from the original signal. The second procedure is to cancel ECG's QRS-T complex from median filtered signal to get P-wave candidate. Before we subtracted the templete from QRS-T complex, we estimated the best matching between templete and QRS-T complex to minimize the error. Then, wavelet transform was applied to confirm P-wave. In particular, haiti wavelet was used to magnify P-wave that consisted of low frequency components and to reject high frequency noise of QRS-T complex cancelled signal. Finally, p-wave was discriminated and confirmed by threshold value. By using this method, We can got the around 95.1% P-wave detection. It was compared with contextual information.

• Bulletin of the Korean Chemical Society
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• v.16 no.10
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• pp.929-933
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• 1995

The electronic band structure and electrical properties of KMo4O6 containing chains of condensed molybdenum octahedra are analyzed by means of the extended Hu&ckel tight-binding method. KMo4O6 has partially filled bands of 1D as well as 3D character. They also exhibit the anisotropic band dispersions with bandwidths much larger along the c* axis than along the directions perpendicular to it. Thus, conduction electrons are essentially delocalized along the c* direction (i.e., the chain of condensed molybdenum octahedra) in the solid. The 1D band of two partially filled d-block bands leads to Fermi surface nesting with the wave vector q=0.3c*. The CDW instability due to this nesting is expected to cause the phase transition associated with the resistivity anomaly at low temperature. The characteristics of metallic behavior in the crystallographic ab plane are explained on the basis of the unnested 2D Fermi surfaces.

• Journal of Electrodiagnosis and Neuromuscular Diseases
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• v.20 no.2
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• pp.135-138
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• 2018

Peroneal neuropathy scarcely can develop after massive weight reduction. A 21-year-old man complained left foot drop after 28% weight reduction (from 94 kgs to 67.5 kgs). During previous seven months, he played PC games with sitting cross-legged more than seven hours a day. In addition, he started a heavily restricted diet three months ago. Except for those, he had neither any medical history nor trauma to his knee. Electrophysiologic study showed the partial conduction block of left peroneal neuropathy at the fibular head. Four-week well balanced diet and physical therapy improved his foot drop. For the prevention of peroneal neuropathy related to weight reduction, well balanced diet and lifestyle modification are needed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.440-447
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• 2020

Masonry structures are used as bearing walls in small buildings, but they are generally considered non-bearing walls. They are used as partition walls that divide the interior spaces of the frame structures of buildings. In addition, wetting techniques that use mortar as an adhesive between blocks or bricks in construction are vulnerable to climatic conditions, especially cracks in mortar, which can cause conduction collapse of the walls in seismic loading. The purpose of this research was to propose a dry concrete block construction method that complements the weak axial shear stiffness and improves the weakness of the wet construction method as well as to investigate its structural behavior. In this study, the material properties of concrete blocks were examined, and the seismic performance of the proposed dry assembly structure was verified by structural behavior tests on horizontal cyclic loads. First, in these study results, concrete blocks can be applied to the dry block construction method instead of wet construction methods because they secure more than C-type blocks in KS regulations. Second, the structural performance of the wall against a horizontal cyclic load indicates that the resisting force of the assembly block wall is increased by increasing the horizontal length of the wall, forming several diagonal cracks. Finally, the proposed dry block wall structure requires a seismic performance assessment considering that the ratio of the shape of the wall by height and length is considered a major influence variable on the structural behavior under a horizontal load.

• Journal of The Korean Society of Clinical Toxicology
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• v.2 no.1
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• pp.7-11
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• 2004

Purpose: We would evaluate the cardiovascular manifestations of the patients with acute organophosphate and carbamate poisoning in the emergency department. Methods: This was retrospectively studied with the review of patient's charts, included total 38 patients were admitted during the past two years in the emergency department of Yeungnam university hospital with the diagnosis of organophosphate or carbamate poisoning. Results: Cardiovascular complications were variously developed in many patients. Electrocardiographic findings were as follows; 4 ($10.5\%$) cardiac arrhythmias included 1 cardiac arrest caused by ventricular fibrillation, 14 ($36.8\%$) sinus tachycardias, 3 ($7.9\%$) sinus bradycardias, and 17 ($44.7\%$) normal sinus rhythms. Conduction disturbances were 23 ($60.5\%$) like as prolonged QTc, 4 ($10.5\%$) ST-T changes, 2 (5.3%) first degree AV block, and 3 ($7.9\%$) right bundle branch block were shown. Other cardiovascular complications were 22 ($57.9\%$) hypertensives, 4 ($10.5\%$) hypotensives, 15 ($39.5\%$) tachycardias, 2 ($5.3\%$) bradycardias, 18 ($47.4\%$) hypoxemics, 12 ($31.6\%$) metabolic acidosis, and 9 ($23.7\%$) pulmonary edemas. Sixteen patients ($42.1\%$) needed ventilatory support because of respiratory paralysis. No patients died in hospital and 36 ($94.7\%$) patients were alive-discharged. Conclusion: Cardiovascular complications are variously in patients with acute organophosphate and carbamate poisoning. Especially, some findings included ventricular arrhythmias, QTc prolongation, hypoxemia, acidosis, and blood pressure changes are known as major precipitating factors to increase the mortality. So, intensive support and aggressive treatment are needed in patients shown various cardiovascular manifestations in the emergency department.

• Journal of Chest Surgery
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• v.33 no.2
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• pp.139-145
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• 2000

Background: The purpose of this study is to review the clinical course after the correction of noncomplicated ventricular septal defect and to analyze the morbidity and risk factors of postoperative complications and evaluate residual defect during the follow-up period. Material and Method: From September 1994 to June 1998 24 patients(median age 10 months) underwent surgery under the diagnosis of ventricular septal defect. We made a retrospective review of the clinical records including the operation notes critical care unit records echocardiography results and the follow-up records. Result: There was no early mortality nd late mortality. There was no postoperative complete conduction block. Respiratory complication was the most common complication. The body weight age type of ventricular septal defect associated anomalies and operative procedure were not related to the incidence of complications. residual ventricular septal defects aortic valve regurgitation and tricuspid valve regurgitation were insignificant in postoperative hemodynamics, Conclusions: Correction of the noncomplicated ventricular septal defect was done without mortality and complete heart block. Aggressive preoperative medical treatment and early surgical treatment may decrease postoperative complications. Postoperative residual shunt and tricuspid regurgitation were not problematic during the follow-up

• International Journal of Arrhythmia
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• 제18권2호
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• pp.66-76
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• 2017

Background and Objectives: Although an anterior linear ablation is an effective lesion set in radiofrequency catheter ablation (RFCA) for longstanding persistent atrial fibrillation (L-PeAF), its durability for bidirectional block (BDB) is only about 60% at repeat procedure. We hypothesized that changes in electrocardiogram (ECG) may predict an anterior line block state and the clinical outcome of L-PeAF ablation. Subjects and Methods: We studied 304 L-PeAF patients (77% male, $60{\pm}10yrs$), who consistently underwent RFCA Dallas lesion set (circumferential pulmonary vein isolation, posterior box lesion, and anterior line) protocol with subsequent comparison of pre-procedural and post-procedural P wave axes, and one year follow-up (n=205) sinus rhythm (SR) ECGs. Results: 1. P wave axis shifted inferiorly at immediate post-procedure (p<0.001), and was independently correlated with BDB of anterior line (${\ss}=10.4$, 95% confidence interval [CI] 2.79-17.94, p=0.008). 2. The degree of post-procedural inferior shift of P wave axis did not reflect clinical recurrence within one-year (n=205, p=0.923), potentially due to conduction recovery of an anterior line. However, among 160 patients without clinical recurrence within one-year, P wave axis at one-year ECG was independently associated with very late recurrence of AF after one-year (n=160, hazard ratio [HR] 0.98; 95% CI 0.97-0.99, p=0.001), during $45.6{\pm}16.7$ months of follow-up. 3. Among 22 patients who underwent repeat procedures, P wave axis shift was more significant in patients with maintained BDB of an anterior line than in those without (p=0.015). Conclusion: An inferior shift of P wave axis reflects the achievement and the maintenance of an anterior line BDB, and is associated with better long-term clinical outcome after catheter ablation for L-PeAF based on Dallas lesion set.